‘Why is the future of Carbon Capture as a Low Carbon technology promising?’
Global warming and climate change concerns have triggered global efforts to reduce the concentration of atmospheric carbon dioxide and greenhouse gases.Almost two years after the signing of the Paris Arrangement to keep normal worldwide temperatures from rising by two degrees Celsius, the world proceeds with its earnest quest for cost-effective methods of reducing greenhouse-gas (GHG) emissions. Indeed, even the astounding development of sustainable power source presumably won't compensate for the normal increase in emissions from other sources. Probably, remaining under the 2-degree limit will require the turn of events and quick reception of cutting edge innovations.
According to the Emission Database for Global Atmospheric Research global emission of CO2 was 33.4 billion tonnes in 2011, which is 48% more than that of two decades ago. Over the past century, atmospheric CO2 level has increased more than 39%, from 280 ppm during pre-industrial time to the record high level of 400 ppm in May 2013 with a corresponding increase in global surface temperature of about 0.8 o C. It is estimated that global GHG emission in 2030 will increase by 25–90% over the year 2000 level, with CO2- equivalent concentrations in the atmosphere growing to as much as 600–1550 ppm. (Leung,Caramanna and Maroto-Valer, 2014)
A few industrial applications for capturing the CO2 and greenhouse gases are already in play.It is widely accepted that greenhouse gas emissions, especially CO2 , must be significantly reduced to prevent catastrophic global warming.
Carbon capture and reliable storage (CCS) is one path towards controlling emissions and serves as a key component to climate change mitigation and will serve as a bridge between the fossil fuel energy of today and the renewable energy of the future. A lot of different approaches has been considered and practised by various countries to reduce their CO2 emission. While practising for different technology the CCS technology looks more promising than any other technology to reduce the CO2 emission and also CO2 can be capture from the atmosphere through direct air capture (DAC) process.
Carbon capture and storage (CCS) has for quite some time been viewed as one innovation with the possibility to reduce GHG emissions significantly. The fundamental thought is to gather carbon dioxide gas and keep it underground. CCS hasn't got on, nonetheless, because it is costly. Yet, another bend on the idea may change its cost profile. In the event that carbon dioxide could be put to industrial use, the subsequent incomes could make carbon capture financially viable.
Future Significance of Carbon capture.
New technologies could reduce carbon dioxide emissions to the atmosphere while still allowing the use of fossil fuels. Developing large scale CCU technologies won’t be easy. One of biggest challenge is, carbon dioxide is highly inert molecule due to which transforming the captured gas into industrial product will require a lot of energy. There are some new applications for captured carbon dioxide are which can be implemented and others are in the developmental stage. Some applications are proven very successful to reduce emissions and generate revenue such as, fuel production, concrete enrichment, and power generation.
Fuel made from captured carbon
There are few methods to produce fuel from captured carbon one of them involves a chemical reaction between hydrogen and carbon monoxide molecules to generate hydrocarbon chain which will produce liquid fuels. Another method is to use microorganism to power the necessary chemical reactions. Microorganism have tendency to observe carbon dioxide during photosynthesis, which produces sugars such as glucose. Some microorganism can further ferment the resulting
sugars into ethanol. Other microorganism produces lipids, which contain hydrocarbon component which can be refined into liquid fuel.
Concrete enriched with captured carbon
Concrete is made up of different materials and cement is the major materials used for binding the concrete. Cement manufacturing generates roughly 8 percent of carbon dioxide globally.Captured carbon can be used to strengthen the concrete. The gas can be used to make carbonate mineral aggregate that goes into concrete but this technique is not promising as the natural aggregate us quite expensive. Other than this one promising approach is there know as “carbon curing” it involves infusing wet concrete with carbon dioxide. Carbon curing will produce concrete which will contain 4 percent of carbon dioxide, by mass.
Power generation using supercritical carbon dioxide
As research has been done for using carbon dioxide to run the turbine more efficiently to generate power which will reduce GHG emissions. As per the study, a conventional cycle using steam will roughly convert 33 percent of the energy in fuel to electricity, but by using super critical carbon dioxide can boost the energy conversion rate to 49 percent. Steam cycles is powered by fossil fuel to generate electricity for more than a century. But the carbon dioxide-based cycles in which Co2 is heated and pressurised into supercritical fluid and transfer heat more readily and will consume less energy to compress the steam, which will make power generation more efficient. There are some pros and cons of the technology like cost effectiveness, replacing the current plant equipment’s and many more which restrict the approach for commercial use
but the potential of the technology is worth watching. (Why commercial use could be the future of carbon capture, 2020)
Many efforts have been taken to commercialise these three uses for carbon dioxide are still in their early stage
Direct air capture
Beside these three technologies, the direct air capture (DAC) of carbon dioxide is emerging rapidly. As DAC is a commercially active geo-engineering technology, the fossil fuel industry is attracted to DAC because the captured CO2 can be used to for Enhanced Oil Recovery (EOR), especially where there is not enough commercial CO2 available locally.
The first industrial DAC plant have been established in Switzerland which is capable of removing 900 tonnes of carbon dioxides from ambient air annually by looking at the potential many more plants is been in progress which will help to reduce the emissions immensely. (Morris, 2020)
Direct air capture of carbon dioxide also helps to produce bio-fuels, e.g. through micro algae cultivation. Algae observe carbon dioxide and convert it into bio-fuel which leads to consume CO2 , there are lot of practise going on for algae production in ponds using different process and technology and trying to make it cost efficient too.